LiftMaster 8557 8557 Manual - Page 35

Troubleshooting Diagnostic Chart Your garage door opener is programmed with self-diagnostic capabilities. The UP and DOWN arrows on the garage door opener flash the diagnostic codes. DIAGNOSTIC CODE Up Arrow Flash(es) Down Arrow Flash(es) 1 1 1 2 1 3 1 4 1 5 1 6 2 1-5 3 2 3 3 SYMPTOM SOLUTION The garage door opener will not close and the light bulbs flash. The garage door opener will not close and the light bulbs flash. The door control will not function. The garage door opener will not close and the light bulbs flash. Door moves 6-8" stops or reverses. No movement, only a single click. Opener hums for 1-2 seconds no movement. Door coast after it has come to a complete stop. No movement or sound. Unable to set the travel or retain position. The battery status LED* is constantly flashing green. Safety sensors are not installed, connected or wires may be cut. Inspect sensor wires for a disconnected or cut wire. There is a short or reversed wire for the safety sensors. Inspect safety sensor wire at all staple points and connection points and replace wire or correct as needed. The wires for the door control are shorted or the door control is faulty. Inspect safety sensor wire at all staple points and connection points and replace wire or correct as needed. Safety sensors are misaligned or were momentarily obstructed. Realign both sensors to ensure both LEDs are steady and not flickering. Make sure nothing is hanging or mounted on the door that would interrupt the sensors path while closing. Manually open and close the door. Check for binding or obstructions, such as a broken spring or door lock, correct as needed. Check wiring connections at travel module and at the logic board. Replace travel module if necessary. Manually open and close the door. Check for binding or obstructions, such as a broken spring or door lock, correct as needed. Replace logic board if necessary. Manually open and close the door. Check for binding or obstructions, such as a broken spring or door lock, correct as needed. Replace motor if necessary. Program travel to coasting position or have door balanced by a trained technician. Replace logic board. Check travel module for proper assembly, replace if necessary. Battery backup charging circuit error, replace logic board. *(if applicable) 35